Printing form and method of preparing the same



E. SAUER June 30, 1931.

PRINTING FORM AND METHOD OF PREPARING THE SAME Filed Nov. 26, 1927 2 TL QJ EVE I7 75 1 1 x765 Fa/a ex Patented June 30, 1931 UNITED STATES PATENT OFFICE ERNST SAUER, OF SCHLOSS KAIBITZ, GERMANY, ASSIGNOR TO THE ERNST SAUER PROCESS, INC.

PRINTING FORM AND METHOD OF PREPARING THE SAME Application filed November 26, 1927, Serial No. 236,021, and in Germany December 7, 1926.

This invention relates to a form for use in printing and to a method of preparing the form.

In the preparation of intaglio printing forms as practiced today, one method is to prepare a positive on the sensitizedmetallic surface, zinc, copper, or the like and etch the surface with acid. Before the surface can be re-used, the etching must be removed, the

0 surface ground and polished and regalvanized.

In contrast with such a method as above described, the present method replaces copper intaglio printing, is much simpler to perform, and results in a considerable saving of time, labor and material.

One method is illustrated in the accompanying drawings, in which, Figure 1 is a side view of a photographic plate and a sensitized gelatine film or plate in position for printing with a screen plate in between.

Figure 2 is a side view of the printed gelatine film or plate.

Figure 3 is a side view of a bath for treating the gelatine film or plate.

Figure 4; is a side view of the treated gelatine film or plate in relief.

Figure 5 is an enlarged fragmentary View of the treated gelatine film or plate before removal of the film of treating liquid.

Figure 6 is a side view illustrating the method of transferring an impression of the gelatine film or plate relief to a celluloid form.

Figure 7 is a side view of the embossed celluloid form.

The reference numeral 1 indicates a gelatine film or plate having a light sensitized upper surface 2 preferably of chi-ornate treated gelatine. A photographic plate or film 3 bearing the negative of the picture is superimposed upon the sensitized surface 2 of said gelatine film 1 and if an inta-glio printing form is to be produced, an intaglio screen 4 is printed down upon the surface 2 in a separate operation. The screen 4 is not essential to my process.

By this method, there is produced on thefilm 1 a relief 5 corresponding exactly to the picture on the photographic plate when the thus exposed and developed film or plate 1 is immersed in a water bath 6 (Figure 3) for a few minutes. The stronger the light that has acted upon the sensitized surface 2, the more are the corresponding points of the surface hardened or tanned and the less intense the-light that has passed through the photographic plate, the less hardened are the points on the surface so exposed, so that upon treatment with water, the film or plate 1 absorbs at the corresponding places more or less water and the copy relief 7 thus formed.

Since the intaglio screen applied in the second exposure has clear transparent lines 8, these lines once printed and developed on the surface 2 are so strongly hardened that they absorb scarcely any water in the water bath and consequently remain in the surface 2 as deep grooves 8 (shown in exaggeration in. Figures 3 and 4) between the dark spots.

The copy relief 7 so formed is freed of the surface film 10 of water by rubbing with a cloth and then rubbed over with amyl acetate and this also removed by a cloth or the like. The water on the surface and in the very fine deep grooves 8 may bestbe removed by an air blast or by a vacuum cleaning device.

The thus prepared copy is used to emboss upon celluloid or the like as shown in Figure 6. The film or plate 1 hearing the copy relief 7 is placed upon a smooth, even plate 11 of metal, glass or the like and a solvent such as acetone or amyl acetate, adapted to soften celluloid, poured over one end of the face of film or plate 1. One end of a celluloid plate 13 is then placed over that portion of plate 1 which has been treated with the solvent and a roll 14 pressed down against the upper surface of the celluloid plate 13. The cylinder 14 is then rolled forward in the direction of the arrow (Figure 6) to force the plate 13 into intimate contact with plate or film 1. The solvent is thusforced into the fine grooves 8 and the air expelled. At the same time, the under surface of plate 13 is rendered plastic by the solvent with the result that a fine impression of the relief copy 7 is made in plate 13. v

In this condition, the plate 13 and film 1 are left for about 15 minutes, by which time the embossed surface of the plate has become solidified. It is then stripped from the film 1 and is'ready for use as a prepared printing form as indicated by the reference numeral 16.

This printing form 16 may either be formed as above by use of a cylinder 1a or by a squeegee or similar device pressed against the celluloid plate 13 and drawn thereover to form the impression in the plate. Since the plate 13 does not adhere to the gelatine form 1, it is easily removed after it is solidified and takes a sharp impression of the copy relief.

It will thus be apparent that I have provided a simple and comparatively cheap method of preparing printing forms.

I claim as my invention:

1. In the process of preparing printing forms from a gelatine copy relief that has been developed, hardened and swollen with water, the steps that comprise placing a solvent of celluloid upon the gelatine copy relief, forcing a plate of celluloid into intimate contact with the copy relief and solvent whereby it is rendered plastic by the solvent and takes a sharp impression of the copy relief and drying the celluloid plate.

2. In the process of preparing printing forms from a gelatine copy relief that has been developed, hardened and swollen with water, the steps that comprise applying a solvent of celluloid to the gelatine copy relief, rolling a sheet of celluloid into intimate contact with the solvent and copy relief, whereby the sheet is rendered plastic by the solvent and receives a fine impression from the copy relief, drying the celluloid sheet and stripping it from the copy relief.

3. The process of preparing a printing form from a gelatine copy relief, which comprises treating said copy relief with a solvent for a solid mass, forcing said solid mass into contact with said copy relief, whereby said solid mass is rendered plastic by said solvent and takes a sharp impression, and forming said impressed mass into a solid printing strip.

4. The process of preparing a printing form from a gelatine copy relief, Which comprises treating said copy relief with a solvent for cellulose esters, forcing a cellulose ester mass into contact with said copy relief, whereby the mass is rendered plastic by said solvent and takes a sharp impression, and forming the impressed mass into a solid printing strip.

5. In the process of preparing printing forms from a gelatine copy relief that has been developed, hardened and swollen with water, the steps that comprise applying acetone to one end of the gelatine copy relief, rolling a sheet of celluloid into intimate contact with said copy relief whereby the celluloid sheet is rendered plastic by the acetone mum:

and receives a fine impression of the copy relief, drying the celluloid sheet and stripping it from the copy relief.

Signed at rankfort-on-the-Main, Germany, this 17th day of November, A. D. 1927. 70

' ERNST SAUER. 

